The food processing industry has long recognized the desirability of seasoning snack foods, such as potato chips, in a consistent and even manner. This industry has thus recognized that significant cost savings and increased customer satisfaction can be obtained when each chip from a bag of potato chips is consistently and uniformly coated with the seasoning. As with other industries, the food processing industry is also interested in reducing costs by utilizing equipment which performs improved functions or performs the same functions at a lower cost than existing equipment. Moreover, the food processing industry recognizes that equipment components which contact the product should be configured for ease of cleaning, thereby maintaining the desired sanitary conditions for handling food products.
There are numerous problems that exist with current equipment and techniques for seasoning snack foods. As a primary example, existing equipment and techniques do not correctly match the desired amount of seasoning added to the incoming product flow. Current seasoning equipment relies upon the applied seasoning mass (weight) to be matched to the mass (weight) of the incoming product in an attempt to achieve the desired proportion of seasoning to the incoming product flow. This technique thus measures the weight of the product and in response thereto applies the selected amount of seasoning, although the industry recognizes that the customer is judging the appearance and taste of the chips based on area of product covered by the seasoning. This difference is critical for incoming products with a varying density. Since the density of the incoming snack food product before seasoning may vary by as much as twenty percent (20%) or more, the chip producer normally under-seasons or over-seasons, depending on the varying difference between the density of the incoming product and the density of the “base product” which matched the desired amount of seasoning. Since the weight of the seasoning may not be insignificant to the weight of the overall product, and since seasoning is recognized as either the most expensive raw ingredient or one of the most expensive raw ingredients in most snack food products, the over-application of seasoning by a producer or the loss of business based upon under-seasoning represents millions of dollars each year to the food processing industry.
For most snack food products, the area of product to be covered by the seasoning to meet the customer's appearance desires is known to be closely related to the volume of the incoming product to be seasoned. Thus conventional seasoning equipment, which weighs the incoming product, has attempted to “estimate” the volume of incoming product based upon measured weight and various other factors and formulas. These derived volumetric numbers are, however, inherently based upon weight measurements. The incoming product is conventionally weighed by a scale which may be built into the incoming product conveyor. The food processing industry has thus long desired techniques which would reliably measure the volume of the incoming product so that seasoning could be more accurately applied to produce the desired amount of seasoning on the area of the individual chips.
Current methods of checking the actual seasoning applied to the chip rely on taking a weight-based sample of a base product, applying a weight-based sample of seasoning and then monitoring the color or salt content of this mixture against periodic samples taken during a production run. Thus, even the method of checking the applied seasoning continues to rely upon weight-based correlations, although it is known that the area of chip closely matches the volume of the product, and thus a volumetric measurement system would be more accurate than a weight-based system.
Another problem with seasoning systems is that the seasoning is not evenly dispersed over the area of the product. Seasoning is conventionally brought to the incoming product through a tube attached to the end of an auger, with a row of holes in the tube that allow the seasoning to be pushed out by the auger and thus fall over the incoming product. These tubes must be continually monitored to insure that the holes do not clog. It is also difficult to correctly use this equipment so that the seasoning is dispersed over the entire area of the incoming product. In addition, these tubes must have their settings manually changed as new seasonings are used due to the seasoning granule style and its affect on seasoning flowing out of the adjustable holes in the tube.
Continued problems with the application of seasoning using the above auger have led to the use of a vibratory conveyor tray with a bias cut discharge to apply the seasoning. Use of this vibratory scarf plate avoids the necessity of using a tube with adjustable holes. This solution, however, creates new problems since the vibratory conveyor that moves the incoming product is the motion that moves the seasoning on the scarf plate. Varying product density has a significant effect on the travel rate of a product being moved with a vibratory conveyor, and accordingly the time shift between the measurement of the base product and the application of seasoning to that measured product causes a mismatch between the seasoning and the base product. Moreover, vibratory conveyors tend to develop a build-up of seasoning over time and therefore have sanitation problems or flow problems due to uneven dispersion. To eliminate this time shift, a second separate vibratory drive has been used to move the scarf plate, so that the travel rates of the base product and the seasoning could be more evenly matched. This separate drive mechanism for the scarf plate increases the cost, weight, and complexity of the seasoning system, and also prevents the system from being easily cleaned, particularly during seasoning change operations.
Tumblers are conventionally used to mix the incoming product and the seasoning. Many of these rotating drums are fabricated from stainless steel, although some newer drums have been fabricated from hard plastic. While these tumbler drums effectively mix the base product and the seasoning, current drum technology also causes undesirably high product breakage.
Some products, such as tortilla chips, require oil to be sprayed on the product prior to the application of seasoning. If the seasoning and oil spray operations were performed in the same tumbler, cleaning the tumbler becomes very difficult because seasoning and oil tend to cake in the drum. It is desired therefore to apply oil upstream of the seasoning operation. Accordingly, an upstream tumble drum for mixing the product with the oil and a downstream tumble drum for mixing the oiled product with the seasoning has been used, although this again increases equipment costs. Moreover, the additional second drum requires the sacrifice of a vertical elevation in the product line, representing the height of the product incoming to the additional drum verses the height of the product discharged from that drum. The addition of this second tumble drum to a product line may thus adversely affect the height of the product as it moves through the food processing system. Also, the addition of another piece of equipment to an existing system may create problems with the increased product travel length of the new system.
Finally, and perhaps most importantly, significant problems exist between the seasoning system and downstream equipment, such as scale and bagging equipment. Generally, the food processing industry does not utilize systems which provide for real time monitoring of activities and changes to the operation of the food handling mechanisms to optimize the system. Conveyor systems which feed the downstream scale or bagger are conventionally turned “on” or “off” in response to either an on/off signal or a modulating signal from the scale or bagger. Steady state run time is important to providing consistent seasoning. To maximize the amount of steady state run time, the upstream conveyor system desirably allows for small amounts of accumulation of product within the conveyor system. Since the prior art conventionally uses only a feedback system, however, neither the upstream seasoning system nor the distribution system achieves the proper flow-of product to the downstream scale or bagger.
The disadvantages of the prior art are overcome by the present invention, and an improved seasoning system and method of seasoning food products, such as chips, is subsequently disclosed which overcomes many of the problems of prior art seasoning systems and techniques.